I've got 2 laptops running Quantal 32-bit, one with a 2nd gen Core i5 and another with a 3rd gen Core i3. On my i5 laptop, Docky in 3d mode produces a translucent green artifact on both the left and right side while moving my cursor over the icons (with or without zoom enabled).
From what I've read on this forum and others, it seems to be a driver issue. However, both my laptops are using the i915 driver and the issue does not occur on my i3 laptop at all.